| Surface Plasmon Polaritons(SPPs) is a kind of electromagnetic modes which excited by the interaction between photons and free electrons on the surface of metal. The SPPs are widely used in the field of photonic device, biosensor and designing of novel material. By using SPPs, a novel route to enhance the light absorption in solar cell has been developed in recent years. The SPPs has more advantages than traditional technique of light trapping. However, SPPs is usually excited by noble metal nanoparticles, such as Au or Ag, which will restrict their application due to the high cost. As a result, the investigation of SPPs excited by low cost metal nanoparticles is crucial. In this thesis, we use Al and Cu nanoparticles to excite SPPs instead of Au and Ag. And the light trapping application of Al and Cu SPPs in solar cells was also studied. The main works are as followings:(1) Finite Difference Time Domain(FDTD) method was used to simulate the SPPs of metal nanoparticles arry. The effects of the size, coverage and medium environment of Al or Cu nanoparticles on the SPPs were studied systematically. And the comparison study with Au and Ag was also performed. The results show that the resonance wavelength of the SPPs can be changed effectively by adjusting the size, coverage or medium environment of the particles. Under the same condition, the resonance wavelength of Al SPPs is in ultraviolet region, which can avoid optical loss caused by Fano effect. Moreover, the scattering efficiency of Al particles is much greater than that of Au and Ag. As a result, Al nanoparticles show great potential for light trapping application in the front electrode of solar cell. In order to be more consistent with the actual situation, the SPPs of ellipsoid particles and metal@metal oxide core shell structure were simulated.(2) We constructed metal particles/AZO/Si structure and simulated the effects of microstructure of Al or Cu nanoparticle arry on the absorption enhancement of silicon. Based on these results, the light trapping effects of Al and Cu particles arry in the nanocrystalline silicon solar cell were simulated by using AMPS-1D software. And the comparison study with Au and Ag was also performed. The results show that Alparticles demonstrate better light trapping effect than Au and Ag, and the highest enhancement of 29% in short circuit current was achieved.(3) Al and Cu nanoparticles were obtained by dewetting approach, and the influences of annealing parameters and thickness of metal films on the particle size and coverage were studied. And the comparison study with Au and Ag was also performed. The extinction spectra of the four kinds of metal particles were measured, and the trend of experimental results was consistent with that of simulation results.(4) Cu nanoparticles with different size were fabricated on ITO(The transparent conductive film) glass substrate, and their surface morphology, transmittance and haze were characterized. The results show that the particles prepared by annealing of Cu film with deposition time of 10 s demonstrate good haze value and transmittance. A series of AZO thin films were fabricated on quartz, and the photoelectric properties were characterized. Based on the optimization of process parameters, we prepared Al nanoparticles/AZO/Si antireflection structure. The results show that the reflectance of this antireflection structure reduced significantly compared with that of bare silicon. Therefore, Al nanoparticles have great potential to act as antireflection layer in the front electrode of solar cells. |
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